# Solar Tracker

Discussion in 'The Projects Forum' started by sunwarrior1993, Nov 21, 2013.

1. ### sunwarrior1993 Thread Starter New Member

Nov 20, 2012
3
0
Good day, everyone.

I'm finishing high school this year, I have to develop a project to finish my technical course (Electronics, Automation and Computer Science).

My project is a Solar Tracker, with the help of my professors we'll decide if have the chance to insert the X and Y axis for the solar panels.

Let me break it down:
- 6 solar panels, each produces 1.5V, that gives a total of 9V.
- A 9.6V Ni-Cd battery pack will be used to store power, for further experiments in robotics or even powering other devices.
- The battery can be charged by building a Ni-Cd battery charger.

The charger circuit that my professor shared with me has a LM317 Ajustable Voltage Regulator.

However, I'm concerned about the voltage regulation because I won't need it, I suppose.
And also about the energy production, can 9V charge a 9.6V battery in DC?

Any help or guidance will be deeply appreciated.
Thank you .

2. ### MikeML AAC Fanatic!

Oct 2, 2009
5,451
1,066
The open circuit voltage from the panels (when in bright sun) needs to be about 1.5X to 2X the open-circuit voltage of the batteries you are trying to charge. Only other option is to connect the panel output to the input of a step-up Switch Mode Voltage Converter whose output is high enough to charge the batteries. NiCads are charged with a constant-current, but the voltage required will need to go as high as ~12V

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3. ### wayneh Expert

Sep 9, 2010
12,379
3,234
I agree with Mike - you'll need a DC-DC converter to boost the voltage. You can find them cheaply all over e-bay. On the upside, this is more efficient than the LM317 voltage regulator.

Without the boost, the only way you can charge the batteries is to use a switching arrangement whereby you charge the batteries in parallel but then switch them to serial to supply the load. Since your cells are in a pack, this may not be an option.

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4. ### donpetru Active Member

Nov 14, 2008
186
25
• ###### KIT104 - Sistem optic activ de urmarire (a miscarii soarelui).pdf
File size:
471.8 KB
Views:
34
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5. ### Alec_t AAC Fanatic!

Sep 17, 2013
5,971
1,135
I'm puzzled. Your project is a solar tracker, but the details given and your question are about battery charging ??

6. ### ErnieM AAC Fanatic!

Apr 24, 2011
7,436
1,626
Typically once one builds a solar tracker they attach it to a solar panel.

One application of solar panels is to charge batteries.

OK?

7. ### sunwarrior1993 Thread Starter New Member

Nov 20, 2012
3
0
MikeML, wayneh and donpetru: Thank you for the information, I will definitely check out the link and the PDF file.

Alec_T: Yes, my main issue was about the battery charging, but now I understand that I need a higher voltage than the input voltage produced by the solar panels, to charge the battery pack.

I started to do some research about the Boost Converter.